Which cooler for a modded 6950?

They make noise, too.

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doveman
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Which cooler for a modded 6950?

Post by doveman » Fri Jun 03, 2011 10:13 am

I need to get a decent quiet heatsink for my 6950 quite soon as the noise is atrocious.

Thing is, I need something that can cope with a shader unlocked, clocked to 6970 speeds, powertune at +20%, 6950.

Is there anything suitable at the moment for that?

Tzupy
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Re: Which cooler for a modded 6950?

Post by Tzupy » Fri Jun 03, 2011 2:03 pm

Probably the Thermalright Shaman could cope with the heat of the GPU and should be compatible with the 6950.
However, the stock cooler of the 6950 does a better job than the aftermarket coolers for the VRMs.
So IMO if you keep your power draw at ~250W with the unlocked and overclocked 6950, the Shaman should
be able to cool the GPU to ~80C, but you'll fry the VRMs. BTW, which particular 6950 card you have?

m1st
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Re: Which cooler for a modded 6950?

Post by m1st » Fri Jun 03, 2011 8:32 pm

Scythe Setsugen 2 works well. If I turn up my case fans, temps stay within tolerances at the lowest fan speed setting. I can run some tests tomorrow on my rig to give you ideas of temps, just tell me what prog you want me to run to simulate load. Preferably something free haha.

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Re: Which cooler for a modded 6950?

Post by doveman » Sat Jun 04, 2011 1:23 am

Tzupy wrote:Probably the Thermalright Shaman could cope with the heat of the GPU and should be compatible with the 6950.
However, the stock cooler of the 6950 does a better job than the aftermarket coolers for the VRMs.
So IMO if you keep your power draw at ~250W with the unlocked and overclocked 6950, the Shaman should
be able to cool the GPU to ~80C, but you'll fry the VRMs. BTW, which particular 6950 card you have?
I've got this one http://www.powercolor.com/global/produc ... asp?id=313

I think it should stay under 250W, as this article http://www.techpowerup.com/articles/ove ... idcard/159 showed that Furmark only pushed a modded, 6970 clocked, +20% PowerTuned 6950 to 252W.

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Re: Which cooler for a modded 6950?

Post by doveman » Sat Jun 04, 2011 1:47 am

m1st wrote:Scythe Setsugen 2 works well. If I turn up my case fans, temps stay within tolerances at the lowest fan speed setting. I can run some tests tomorrow on my rig to give you ideas of temps, just tell me what prog you want me to run to simulate load. Preferably something free haha.
Thanks. OCCT http://www.ocbase.com/perestroika_en/index.php?Download GPU test will probably do fine. Everyone says Furmark unrealistically loads the card, so I wouldn't bother with that.

If possible, can you test with the card modded, at 6970 clocks but at +10% PowerTune as well as +20%, as I'd be interested to see what difference that makes to power draw and temps. I think the OCCT GPU test gives an average FPS as well, and I'd be interested to know how that differs between +10% and +20% PowerTune too.

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Re: Which cooler for a modded 6950?

Post by Tzupy » Sat Jun 04, 2011 6:00 am

So your card is already not using the stock cooler. Unfortunately I couldn't find a review of this
Powercolor 6950, to see the layout of the PCB and especially the existing VRM cooling (only PCS+ reviews found).
The VRM for the GPU seems to be located on the left, while on the PCS+ version is on the right.
But if the card didn't die yet under extra load, it should be OK with an aftermarket cooler too (I might be wrong though).
The Setsugen2 might have some difficulty cooling the card considering the extra power draw.
OTOH the Shaman is bloody heavy (I already bought one, am undecided which 6950 to put it on).
Would you mind telling me precisely (in mm, if possible) what length the PCB of your Powercolor 6950 is?
That is, not including PCI bracket and cooler overlapping the card, just the PCB itself? Thank you.

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Re: Which cooler for a modded 6950?

Post by m1st » Sat Jun 04, 2011 6:30 am

Done testing and my computer's not on fire :)

Computer specs to establish a baseline:
Core i7-920 @ 4.01GHz, 1.35v
Gigabyte GA-EX58-UD3R rev 1.6
3x2GB OCZ DDR3-1600 @ 1528, 7-7-7-20-1T, 1.64v
XFX Radeon HD 6950, unlocked shaders, 880/1300 (can't get memory stable at true 6970 speeds)
ASUS Xonar DX
ASUS Blu-ray drive
OCZ Agility2 120GB SSD
WD6400AAKS 640GB Hard drive
Seasonic S12II-430 w/ fan swap, Scythe S-Flex 1600rpm
Antec P183
(2) 120mm Scythe S-Flex 1200rpm case fans
120mm Scythe Kama Flow 2 1400rpm heatsink fan
Scythe Kaze-Q fan controller

And results:
Powertune 0%
============

Setsugen fan 5v
Load: 325w
FPS: 200
GPU: 495-880, lots of fluctuating, most of the time spent around 550
GPUTemp: 89,93,95
VReg: 95

Powertune 10%
=============

Setsugen fan 5v
Crash

Setsugen fan 12v
Load: 370w
FPS: 244
GPU: 612-880, lots of fluctuating, most of the time spent around 700
GPUTemp:83,86,89
VReg:98

Powertune 20%
=============
Setsugen fan 12v
Load: 400w
FPS: 256
GPU: 880
GPUTemp: 86,90,92
VReg: 111

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Re: Which cooler for a modded 6950?

Post by m1st » Sat Jun 04, 2011 6:36 am

Image

Here is my card with the Setsugen2 VRM/Mem heatsinks on. My card was a reference card, so everything fit properly. The bar on the right is for nearly all of the VRM components - this piece actually bolts onto the back of the card using screws. If you look to the left of the top row of memory heatsinks, you'll see a crooked heatsink. This is another VRM, presumably for the memory? On this VRM and the memory ones, I took off the stock tape (which is pretty bad) and used Arctic Silver Adhesive.

falcon26
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Re: Which cooler for a modded 6950?

Post by falcon26 » Sat Jun 04, 2011 12:37 pm

I just ordered the MSI Twin Frozr II. I also ordered the Artic Cooling Twin Turbo for it to replace the stock cooler. We'll see how it goes :-) How quiet is the cooler on your 6950?

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Re: Which cooler for a modded 6950?

Post by doveman » Sat Jun 04, 2011 3:44 pm

Tzupy wrote:So your card is already not using the stock cooler. Unfortunately I couldn't find a review of this
Powercolor 6950, to see the layout of the PCB and especially the existing VRM cooling (only PCS+ reviews found).
The VRM for the GPU seems to be located on the left, while on the PCS+ version is on the right.
But if the card didn't die yet under extra load, it should be OK with an aftermarket cooler too (I might be wrong though).
The Setsugen2 might have some difficulty cooling the card considering the extra power draw.
OTOH the Shaman is bloody heavy (I already bought one, am undecided which 6950 to put it on).
Would you mind telling me precisely (in mm, if possible) what length the PCB of your Powercolor 6950 is?
That is, not including PCI bracket and cooler overlapping the card, just the PCB itself? Thank you.
I've got a feeling the card should be reference layout as I understood it was only reference cards that have the dual-bios switch and are flashable to 6970 shaders, but I'll measure it for you when I get a chance.

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Re: Which cooler for a modded 6950?

Post by doveman » Sat Jun 04, 2011 3:58 pm

m1st wrote:Done testing and my computer's not on fire :)
Great job, thanks for doing that and for the picture, that should come in handy when I get to fitting the Setsugen2.

Although OCCT's FPS isn't directly comparable to real gaming, it seems like the extra FPS from going from 10% to 20% Powertune doesn't really justify the large increase in VReg temp, so I'll probably just run it at 10%.

I was slightly surprised that the GPU clock wasn't stable at 10% Powertune, as I had a problem with the clocks fluctuating (and this causing GPU load) in MediaPortal, which was fixed when I set Powertune to 10%, but that was just at stock clocks.

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Re: Which cooler for a modded 6950?

Post by doveman » Mon Jun 06, 2011 3:35 am

OK, I've had a chance to measure the PCB now and it's 240-241mm.

I've noticed a strange thing about my power meter, in that it reads 12W with the PC plugged in but the PSU switched off, and 27W with the PSU switched on, which seems rather wasteful but perhaps that's just normal for PCs.

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Re: Which cooler for a modded 6950?

Post by Tzupy » Mon Jun 06, 2011 4:19 am

Thank you very much. This means it would fit in a Solo with an aftermarket cooler like the Shaman or Setsugen2.
Probably it wouldn't fit in a Solo with the original cooler, which extends past the PCB, but I'm not sure.
Now I have to find a Powercolor 6950 available in Bucharest. Lately the 69xx series have been scarce here.
PS. If you'll be able to post pictures of your card with the VRM and memory sinks installed, that would be great.

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Re: Which cooler for a modded 6950?

Post by doveman » Mon Jun 06, 2011 5:14 am

The heatsink itself seems to only extend about 9mm past the PCB. The plastic surround is about another 10mm, but perhaps this can be cut off at this end?

I haven't purchased an aftermarket cooler yet, so it will be a while before I can post any pictures. Are they likely to look any different to m1st's one anyway, assuming both are cards are reference layout, which I think they should be?

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Re: Which cooler for a modded 6950?

Post by Tzupy » Mon Jun 06, 2011 6:59 am

9 mm past the PCB would still fit in a Solo, but the extra 10 mm shroud would definitely not fit.
Cutting the plastic shroud would be a more obvious warranty violation than replacing the whole cooler.
I might ask a friend with a roomier case to test it for me and then replace the cooler.

My evaluation of the length of the XFX 6950 PCB shown in m1st's picture is that it's about 15 mm longer than yours.
No offense meant, in this case shorter is better! :wink:

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Re: Which cooler for a modded 6950?

Post by doveman » Mon Jun 06, 2011 10:21 am

Tzupy wrote:My evaluation of the length of the XFX 6950 PCB shown in m1st's picture is that it's about 15 mm longer than yours. No offense meant, in this case shorter is better! :wink:
hehe, makes a change :lol:

It'll be interesting to compare my card to m1st's once I get round to changing the cooler. I want to know what that extra 15mm contains that my card doesn't have. Maybe they didn't get the memo saying that shorter is better and they just spread everything apart a bit more :wink:

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Re: Which cooler for a modded 6950?

Post by zyrobs » Wed Jun 08, 2011 5:05 am

I just installed a Setsugen 2 on my 6950 as well. I used pretty much the same setup as on the picture posted above, except that I used the stock adhesive everywhere, and added one-two extra heatsinks on the bigger chips on the board. Also, I didn't use the stock screws for the VRM sink, but some longer ones I had, as that way I can still have the cards stock back board attached.

Pros of the Setsugen 2:
- super silent. Even at max load, it just gives a gentle whoosh, nothing unbearable. Up to until about half load, it's virtually noiseless. Well, I can't hear anything because of the 4 HDDs next to it, which make all the sound in my computer now.
- excellent VRM cooling. On my previous 5850, I used an Accelero S1 + 12cm fan + stock backplate, and the VRMs were always 20-30c above the GPU, generally reaching 90-100c. On this 6950, with the Setsugen 2, the VRMs max at 60-70c. Very good.
- It's very small! All other 6950 coolers take 3 slots minimum, this thing is a little smaller than 2 slots (only by a few mm). I imagine it could be used for Crossfire setups just fine. Well, actually, it wouldn't work in Crossfire, because...

Cons of the Setsugen 2:
- cooling performance is very weak. It may just cope, at maximum fan speed, with a stock 6950 in most games. That means no shader unlock, no overclocking, and no furmark. On my setup with shaders unlocked, running OpenCL apps (hash bruteforcing, which puts higher load than a game but lower than furmark), I hit over 100c almost instantly at which point powertune kicks in (despite the +10% I set it to), and downclocks the card. If I downclock the card to 500mhz, I stay within 90c that the stock cooler is calibrated for.

Needless to say, I'm extremely unhappy with the results. So I'm off to buy an extra 12cm fan to put on this thing, which HOPEFULLY helps the cooler performance. However, that will make the card bigger than 2 slots, making it impossible to use Crossfire, unless your cards have 1 slot of free space between each other!
Or, you can find a faster running slim 12cm fan - I recall one user mentioning that he ordered a Scythe slim 12cm fan that had PWM control, and could get the card to stay at 90c max with furmark using that.

edit: I should also add, that with the stock cooler at 60%, I could get the card to stay at 90c max with 24/7 max load in OpenCL, with shaders unlocked, and the gpu overclocked to 900mhz with the voltage bumped to 1.2v. That was in a full heat wave. Of course, the card did sound like a vacuum cleaner.
Right now, as I measured the Setsugen 2, the temperature is pretty cool in my room, which makes its performance that much unimpressive.

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Re: Which cooler for a modded 6950?

Post by doveman » Wed Jun 08, 2011 6:43 am

Thanks for that. I was a bit concerned about the temps shown in m1st's test. I'm going to wait for someone to test with the Shaman and see if that does a better job. I really expect these aftermarket GPU heatsinks to result in lower temps than the stock cooler, as is the case with CPU heatsinks.

Incidentally, what is everyone using to measure VRM temp, as the GPU-Z I'm using seems to only show 26c all the time!

zyrobs
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Re: Which cooler for a modded 6950?

Post by zyrobs » Wed Jun 08, 2011 8:24 am

GPU-Z 0.5.3 gives me good vreg temp readings.

All right. Installed a full size 12cm fan - some Asus sleeve bearing 1200rpm fan, says the air flow is 60cfm. It's a little noisy, though nowhere near as bad as the stock cooler. The topmost sata connector on my GA-p35-ds3 is now blocked, or at least difficult to use without some cable bending. (if it was a ga-p35-ds3r, there would be 1 blocked Sata ports)

Idle temps were 33c on boot, 42c after a long stresstest.

Still using OpenCL hash bruteforcers that max the card more than games but less than Furmark:
- Load temps, with shaders unlocked, powertune +10% and 840mhz (max overclock from CCC): ~78c gpu, ~82c VRM.
- Load temps, with MSI Afterburner set to 900mhz and 1,2v: ~90c gpu, but VRMs reach as much as ~106c.

I am not yet convinced that this was a good buy.

Edit:
I was doing a third test with the Thermaltake TT-1225 A1225L12S fan that I'm using for intake - Thermaltake gets a lot of shit for their noisy fans, but I found these to be noiseless at 5v and 7v, I have 2 as intake and I had a third on my old 5850 + Accelero S1 that I sold. Since I moved one to the cooler, I now have no intake fan in the machine (antec p183, upper chamber. lower chamber still has one intake fan pointed on the hdds).

- at 7v, at 900mhz 1,2v, the machine crashed as I wrote this edit on the first time. Stock speed was some 70-80c for the gpu, as I recall.
- at 12v, which gives a little whoosh sound, at same clock/voltage, I got 92c gpu and 110c vrm. Not good.
- with card set to the marginally lower 880mhz 1,175v (same speeds as the 6970), 87c gpu and 100c vrm. This is... bearable.

I guess there's just no helping it - the Setsugen 2 is NOT fit to cool the 6950 at complete silence, not by itself and not with alternate coolers either. Of course, it was never advertised as 6950 compatible to begin with. I wonder what the temperatures would be with a Nexus or some other more tried-and-true fan that I have no access to at the moment, they'd probably only shave down 5c or so, unless its some high rpm fan which is also very noisy.
Also, remember that I'm running the card overclocked, with unlocked shaders. That puts a ton of extra work into the gpu. With unlocked shaders and stock clocks, the Setsugen 2 stock oughta be enough, and with an alternate 12c fan, it can even do temperatures far lower than the stock cooler... at much lower noise level. Not to mention if you use a PWM fan, and if you NOT run the card 24/7 on max load.

The bottom line is, the 6950 is a giant of a GPU that's pushing the limits of the 45nm process already. It runs hot, like the 4xxx series did so before it. The upcoming 7xxx series on 28nm will have a much, much, much better chance at giving low temps with no noise, just like the 58xx cards did before.

I have a feeling that an Accelero S1 may cool the card as good as the Setsugen 2, at the expense of space. For that reason, I'm not happy with this Setsugen 2 at all.

Now, my only remaining concern, is that I had the backplate attached to the card. This thing gets VERY hot after running the card! I can't imagine it spreading much of the heat, but I'm a little worried that it heats up other components on the card that would be cooled fine otherwise, or would require no cooling by themselves. Should I remove it?

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Re: Which cooler for a modded 6950?

Post by faustus » Wed Jun 08, 2011 10:44 am

There's no VRM label in GPU-Z for my card (Asus HD 6950 DirectCU II), but there's "GPU #1", "GPU #2" and "GPU #3" with a couple of degrees between them, like 49 C, 50 C, 53 C.

Is it likely that one of them is the VRM temp? Can't see any other temperatures.

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Re: Which cooler for a modded 6950?

Post by doveman » Wed Jun 08, 2011 2:45 pm

Thanks for the update zyrobs.

I'm using GPU-Z 0.5.3 and it actually shows two VReg Temps, but one stays at 0c and the other around 26c!

I've got a spare Accelero S1 rev2 lying around, so if it's as good as the Setsugen 2 I might just try that, but I think I'll wait and see if there's any other heatsinks that work better with the 6950.

faustus, those GPU temps aren't the VRM. I have them too, all quite close to each other. You should see a VReg temp at the bottom. Have you got v0.5.3?

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Re: Which cooler for a modded 6950?

Post by faustus » Wed Jun 08, 2011 3:16 pm

Thanks doveman. Yes, it's v0.5.3; and no, there's no Vreg temp at the bottom (or elsewhere in the "sensors" tab) - the bottommost five fields are the three GPU temps, a "VDDC Offset" voltage and a "Current OCP" percentage.
Is it possible that there's no VRM sensor in this card?

On the VGA cooler: Isn't the Accelero Xtreme Plus II good? It's supposed to be compatible with 6950, and the first version was the Editor's Choice at SPCR for amazing performance and quiet fans.

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Re: Which cooler for a modded 6950?

Post by zyrobs » Wed Jun 08, 2011 4:35 pm

Go ahead and try the Accelero S1v2, chances are it'll be adequate for your needs. What I do with my card is way above what a regular user would throw at the card, I'm basically running the 6950 as a 6970, 24/7 at near-furmark level loads.

A little update. I readded a front case fan, bumped up my other fans a little bit, and I also put in the Scythe fan that came with the Setsugen into the top fan slot of the P183. The machine now runs a wee bit noisier (still considerably more silent than the stock fan of the 6950 at the 60% load I had to throw at it). But, the increased circulation has improved temperatures considerably, and I'm now more satisfied with the results.

Image

I'm going to give a last try tomorrow at running the gpu fan at 7v, to render the machine considerably more silent. If it stays around 85c, I'll leave it like that.

My 6950 is a first gen Sapphire model by the way, bought it back in December, back when the only difference between all vendors was literally the sticker they put at the card. Other, newer models my have different methods for VRM temperatures detections, so they may not show up in
faustus wrote:On the VGA cooler: Isn't the Accelero Xtreme Plus II good? It's supposed to be compatible with 6950, and the first version was the Editor's Choice at SPCR for amazing performance and quiet fans.
I thought of the AC Xtreme Plus, in hindsight it may have been a better choice. I went against it because I disliked the idea of having 3+ small fans versus 1 big, for noise reasons. Also, it would've surely blocked one of the sata ports in my computer - which again is a moot point because it's blocked now anyway. Or at least, hard to access - I've yet to try, the fan itself may be far enough from the board itself that a sata cable may just fit there.

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Re: Which cooler for a modded 6950?

Post by swaaye » Wed Jun 08, 2011 6:35 pm

The Thermalright TRad 2 GTX fits perfectly. It cools the card more than adequately even with those fans on 7v. (I modded the stock baseplate to use as VRM cooling)
Image Image Image Image Image

I initially tried an Accelero S1 but its heatpipes are barely adequate for Cayman in Furmark. It did seem fine games though. BTW the Accelero S1 has a terrible base that doesn't hold it tight to the card. The TRad blows it away here too.
Image Image Image Image

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Re: Which cooler for a modded 6950?

Post by doveman » Thu Jun 09, 2011 12:16 am

Yeah, I was never too keen on the Accelero's mounting and those little plastic clips that are supposed to hold the edges of the board and cooler together, which were never up to the job in my experience.

Is there any chance you could do some tests like m1st did, with OCCT, so that we can see what temps you get with an unlocked, 6970 clocked, +10-20% Powertuned 6950 and the TRad 2 GTX?

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Re: Which cooler for a modded 6950?

Post by SebRad » Thu Jun 09, 2011 5:36 am

Hi, I have an Akasa Freedom Force cooler on my GTX260. Only got it as was the only one, at time, that would fit the card and my case! Big write up.
Lots of effort with it to sort out the VRM cooling etc as got a first revision that came with only 9 heatsinks. (For 14 RAM chips, NVIO chip, 12 VRMs and various other bits!)
I’ve also replaced the fans on it with a pair of Arctic Cooling F9 PWM fans, connected to the card and speed controlled by it. (with modified BIOS fan control curve)
The GTX260 is similar, probably a bit higher, to HD6950 in power consumption. The cooler is rated up to a GTX285 which is high or higher than a HD6970.
My GTX260 is overclocked ~20% and the fans idle at ~625rpm, very (very) quiet. Furthermore unless heavily loaded they don’t increase in speed, PC’s been running folding@home and mostly not increasing the GPU fan speeds! Reported GPU temp in GPU-Z of ~65°C. I’ve been playing Civ V on 1920x1200 high settings sends it up to 72° ~ 75°C, but the fanspeed increase about 72°C
Furmark temps, I think, are held around 80°C with fanspeed approaching 1000rpm, which isn’t that loud.

I don’t know if the cooler will even fit a HD6950 or if it’s a good solution as the 4 “direct touch” heatpipes might not contact too well on the small bare AMD chip, the GTX260 has a massive heatspreader. But it’s another option and widely available in the UK.

Seb

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Re: Which cooler for a modded 6950?

Post by zyrobs » Thu Jun 09, 2011 6:11 am

OK, with the fan set to 7v I get ~89c and 100c VRM. Not good. It's gonna stay at 12v for summer, or until I find a better fan that can push more air at low noise.

I also tried removing the upper hdd bay to improve airflow, but it made no difference.

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Re: Which cooler for a modded 6950?

Post by boost » Thu Jun 09, 2011 7:31 am

There is a way to improve the VRM cooling:
In Russia VRM mods you. :lol:
With the Thermalright VRM-R4 there's a 35 degree drop in temps.

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Re: Which cooler for a modded 6950?

Post by swaaye » Thu Jun 09, 2011 10:05 am

FYI, the 3 temp sensors are all on the GPU die. VRMs are not measured. The temps are 3 different hot spots in the GPU.
doveman wrote:Is there any chance you could do some tests like m1st did, with OCCT, so that we can see what temps you get with an unlocked, 6970 clocked, +10-20% Powertuned 6950 and the TRad 2 GTX?
I compared it with my 6950 unlocked but at stock clocks.

I tried two S1s but both of them would let one of the temps break 100C eventually in Furmark and that's why I gave up on that. There was a 30C difference between the 3 temps! I think one or two of the heatpipes was getting too much heat and overloaded. I tried various fan combinations including 1x120, 2x120, combo 120 and 80, 2x92.

The TRad2 keeps all three temps close and 70-80C even in Furmark with the fans on 7v and basically inaudible. Considerably better results.

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Re: Which cooler for a modded 6950?

Post by doveman » Thu Jun 09, 2011 12:54 pm

It's a shame your card doesn't show VRM temps, as that seems to be the most problematic part of the card to keep cool. The GPU temps seem OK, but without testing with the card overclocked and Powertuned, it's impossible to know whether the cooler is up to the task.

I'll certainly not try the S1 on my 6950 though!

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